A taxonomy of item response models

A number of models for categorical item response data have been proposed in recent years. The models appear to be quite different. However, they may usefully be organized as members of only three distinct classes, within which the models are distinguished only by assumptions and constraints on their parameters. “Difference models” are appropriate for ordered responses, “divide-by-total” models may be used for either ordered or nominal responses, and “left-side added” models are used for multiple-choice responses with guessing. The details of the taxonomy and the models are described in this paper. The present study was supported in part by two postdoctoral fellowships awarded to Lynne Steinberg: an Educational Testing Service Postdoctoral Fellowship at ETS, Princeton, NJ and an NIMH Individual National Research Service Award at Stanford University, Stanford, CA. Helpful comments by the editor and three anonymous reviewers are gratefully acknowledged.     

On the detectability of straight lines in visual noise: An extension of French’s paradigm into the millisecond domain

We report the results of a study that investigated the effects of four experimental parameters on the tachistoscopic detectability of dotted lines in a noisy background consisting of dynamic patterns of identical dots. Characteristics of the lines that were explored included dot spacing, dot numerosity, and line orientation. Dot spacing was shown to be the most powerful parameter in determining the masking effect: the closer the dots, the more easily the line was detected. Increasing the number of the dots was also effective in increasing the detectability of a line, but only up to a limit of five dots. The orientation of the line, on the other hand, did not alter its detectability. Increasing the density of the visual masking noise monotonically reduced the detectability of the line. These studies are an extension of French’s (1953, 1954) work, differing mainly in the fact that the stimulus material was presented tachistoscopically rather than in a mode that allowed prolonged (up to 5 sec) examination of the figures. Thus, they put the results in a domain in which physiological interpretations may be more critically evaluated. A comparison of the results suggests that essentially the same sorts of cognitive mechanisms are operating in the millisecond domain as in the longer exposures. This suggests that simple neurological models utilizing the concept of feature filters or detectors may be being prematurely applied to relatively complex perceptual processes.     

Personality Types and Vocational Choice: A Test of Holland's Theory

In order to test the adequacy of Holland's theory of vocational choice with reference to a broad segment of entering college students, a sample of the freshman class entering the Pennsylvania State University evaluated themselves in terms of the six personality styles of Holland's theory. Relationships between the personality styles and vocational choices were studied for groups of Decided, Tentative, and Undecided students. While several inversions in the data are evident, the data possess sufficient consistency to indicate that the personality identifications these students made in Holland's frame of reference were related to their initial vocational choices.     

The role of observer attitudes in judgments of blame in cases of wife assault

This study examines the importance of observer characteristics in determining blame in cases of wife assault. Four independent variables (observer's attitudes toward sex roles, observer sex and age, and victim behavior) were assessed for their influence on the blaming judgments of 128 participants. Subjects completed a questionnaire that contained demographic items and six wife assault vignettes that varied in level of victim provocation (low or high). Questions about blame of the husband and wife followed each vignette. An attitudes toward women scale (AWS-B) was then administered. The main hypothesis, that subjects with traditional attitudes would blame the victim more and the perpetrator less for the assault than their egalitarian counterparts, was supported, as was the prediction of an interaction between provocation and AWS-B. The results are discussed in light of the role of observer attitudes in attribution models.